Benzodiazepine Anti-Anxiety Agents: Prevalence and Correlates of Use in a Southern Community

Benzodiazepine Anti-anxiety Agents: Prevalence and Correlates of Use in a Southern Community

rn- rn Marvin Swartz, MD, Richard Landerman, PhD, Linda K George, PhD, Mary Lou Melville, MD, Dan Blazer, MD, PhD, and Karen Smith, PhD Introduction alence and patterns of benzodiazepine antianxiolytic drug use in the Piedmont re- Benzodiazepine anti-anxiety agents gion of North Carolina during 1982-83, uti- are the most widely prescribed psycho- lizing logistic regression analysis, which al- therapeutic drugs in the United States to- lows prediction of benzodiazepine use day.' First introduced in 1960, these drugs while introducing controls for potential rapidly achieved a lead position in the pre- confounding and mediating variables. scription drug market,2 stimulating public and professional debate over appropriate Method psychotropic drug use.3 Recent evidence, however, suggests that the prevalence and The present paper reports results patterns of psychotropic use, especially from Wave 1 of the Piedmont Health Sur- those of benzodiazepine anxiolytics, may vey, one site of the five-site National In- be changing and resulting in decreased stitute of Mental Health Epidemiologic use.4,5 The first detailed population survey Catchment Area program (NIMH- of psychotropic drug use, the National ECA).'1 The sampling frame for the Pied- Household Sample in 1970-71,6-9 found mont Health Survey (PHS) was a five- that 22 percent of American adults had county area in north central North used prescription psychotropic medica- Carolina, consisting of one urban county tion during the year 1969-70, with higher and four contiguous rural counties. The use among women and the elderly. The survey randomly sampled all housing most commonly used drug group, "minor units from segments throughout the catch- tranquilizer/daytime sedatives," was used ment area, using the Kish method,14 yield- by 8 percent of men and 20 percent of ing 3,798 interviews usable for this study; women. Use was greater in Whites and in further details of the study have been pub- divorced, separated, and widowed per- lished elsewhere.'5 In this paper analyses sons and the elderly.6 In 1979, the Na- are based on weighted data, taking into tional Survey of Psychotherapeutic Drug account household probability selection, Use documented, using weighted data, nonresponse, and the 1980 census demo- that an estimated total of 8 percent of men graphic proffle of adults in the five-county and 13.7 percent of women had used ben- catchment area. For significance tests, the zodiazepine anxiolytics in the previous data were downweighted to the original number of but year with the greatest use among respon- subjects, weighting adjust- ments remain. dents ages 5(04)42,10 Recent surveys of were obtained through use the St. Louis area population" and Great Diagnoses of the Diagnostic Interview Schedule Britain'2 found lower overall rates of use but similar sex and age usage profiles. Previous studies have relied primar- From the Psychiatric Epidemiology and Health ily on bivariate analyses when describing Services Research Program, Department of patterns of drug use, failing to take into Psychiatry, Duke University Medical Center. account the intercorrelations among pre- Address reprint requests to Marvin Swartz, dictors, including demographic, MD, Box 3173, Duke University Medical Cen- diagnos- ter, Durham, NC 27710. This paper, submitted tic, symptoms, and service use variables. to the Journal March 12, 1990, was revised and In the present study we examine the prev- accepted for publication December 12, 1990.

May 1991, Vol. 81, No. 5 Prevalence and Correlates ofAnidolytic Use

(DIS), a highly structured interview de- entered by stage. This format yields an signed for use by lay interviewers in epi- estimate of the effect of each variable net demiological studies and capable of gen- of all adjacent and prior variables and in- erating computer-based diagnoses for dicates whether the effects of prior varia- certain DSM-III disorders.'6 The diag- bles are mediated by subsequent varia- noses generated by the DIS were too nu- bles. The logistic regression procedure merous to include in a single regression calculates maximum likelihood estimates equation. Preliminary analyses ascer- for the parameters of a model that express tained that an affective disorders sum- the log odds ofan event (here, drug use) as mary measure (consisting of major de- a simple linear model.21"22 pressive disorders, bipolar disorders, dysthynmia, and bereavement), panic dis- Results order, and agoraphobia with panic were most strongly related to benzodiazepine Table 1 presents the demographic use. These measures were retained for profile for subjects participating in the subsequent analyses. The version of the survey.Table 2 focuses specifically on DIS used in Wave 1 of this survey and use of benzodiazepine anti-anxiety other ECA sites did not include one anx- agents-predominantly diazepam and iety disorders diagnosis, generalized anx- chlordiazepoxide-regardless of source. iety disorder, employed at certain ECA All other anxiolytics as well as all seda- sites in follow-up interviews. tives and hypnotics (benzodiazepine and In the present study psychotropic other) are excluded. Table 2 presents a drug use refers to any use within the year cross-tabular analysis of the weighted prior to interview, regardless ofamount or prevalence of benzodiazepine anxiolytic duration ofuse andwas elicitedbyspecific use among various demographic and drug use probes aided by photographic other groups of interest. For two contin- drug identification cards. Other measures uous variables, correlation coefficients used for this analysis include a 29-item are used: the correlation coefficient of psychic distress scale analogous to the drug use with number of negative life SCL-90,17 and the number of negative life events is .09 (p < .01) and that for drug events during the year prior to the inter- use with psychic distress symptoms is .20 view, measured by a scale of 20 major (p < .01). Benzodiazepine anxiolytic use events of the type proposed by Holmes is more prevalent among women, older and Rahe.18 Analyses of life events in the persons, Whites, and those with less ed- survey have been published else- ucation. The never married and married where.'9'20 Interviewers also recorded the have significantly lower prevalence of numberofoutpatientvisits to physical and use than the divorced and widowed. Re- mental health providers during the six spondents who have recently used either months prior to interview. The measure of physical or mental health care services outpatient health service utilization em- are much more likely to use these agents, ployed in this study is dichotomous, be- as are those with a DIS diagnosis of af- cause the use vs non-use measure has fective disorder, panic disorder, or ago- more explanatory power than a continu- raphobia with panic. ous (number of visits) measure. Demo- Table 3 presents results ofthe logistic due to higherlevelsofpsychic distress and graphic variables used in this report in- regression analyses. The "OR" coeffi- health service utilization among women. clude sex, age, race, education level, cient in the table is the antilogged regres- The race effect changes very little across marital status, and urban vs rural resi- sion coefficient and estimates how stages indicating no substantial effect of dence. Income is excluded because pre- changes in the independent variables mul- potential mediating variables. While the liminary analyses indicated that the rela- tiply the odds of using benzodiazepine coefficients for age fluctuate across stages, tionship between anxiolytic use and anxiolytics, holding other variables in the they remain largely unmediated and sub- income is weak. equation constant. Ninety-five percent stantial at stage VI. In stage II, increases The Appendix presents a six-stage confidence intervals are also given. The across each of four levels of education (as causal model predicting the dichotomous overall fit of the model is assessed by R indicated in Table 2) reduce the odds of measure of use vs nonuse of benzodi- statistic which is roughly analogous to the benzodiazepine use by .9. This initial ef- azepine anti-anxiety agents. A unidirec- multiple correlation coefficient in ordinary fect decreases in stages IV and V, indi- tional causal process is assumed with var- least squares regression after correcting cating that those with more education use iables in prior stages affecting those in for the number ofparameters estimated.22 benzodiazepines less, in part, because subsequent stages. No causal direction is In stage I, older persons and women they have fewer DIS diagnoses and psy- assumed for variables in the same stage. are both more likely than others to use chic distress symptoms. Compared to the In the multivariate logistic regression anal- benzodiazepines, while Blacks are less never married, the separated, divorced, ysis below, effects of the stage I variables likely. The gender effect decreases sub- and widowed are more likely to use ben- are estimated first, and the equation is stantially in stages V and VI indicating zodiazepine anxiolytics. These marital then expanded as groups of variables are that much of the initial sex difference is status effects are not mediated by varia-

May 1991, Vol. 81, No. 5 American Journal of Public Health 593 Swartz et al.

education, previously thought to be predictors ofanxiolytic use, exert theireffects indirectlyvia theirrelationshipswith other predictors in subsequent model stages. The effect of education is mediated by intervening factors such as high levels of psychic distress or stressful life events. Women indeed use more anxiolytics, but probably because they either have or report more distress than men and/or are more likely to seekhelp. That is, net ofthe effect of increased levels of psychic distress and help-seeking among women, women are no more likely than men to receive and/or use anxiolytics, indicating less evidence for sex bias in prescnbing practices and use than suggested in previous studies and the press.1'23-25 One ofthe most important findings in the present study relates to increased anxiolytic use in the elderly, many of whom are already medicated and/or cognitively impaired.2 Benzodiazepine use in the elderly is a particular concern because the use of long half-life benzodiazepines such as the ones included in the present study is associated with an increased risk of hip fracture,26 creating a potentiallyfatal com- plication of anxiolytic use in this population. High levels ofuse in the elderlyraises concerns about the judicious use of these agents. The differential rates ofanxiolyticuse by race, lower among Blacks even when predictors such as use of health services are controlled, cannot be explained further in the present analysis. These results do suggest possible racial bias in prescribing practices and/or different modes of help-seeking and alleviation of psychic distress among Whites vs Blacks. Prior studies have demonstrated that separated or divorced respondents have higher levels of life stress and psychic distress9 and are more likelyto use anxiolytics, presum- ably as a result of these stressors.6,9 Our analyses suggest, however, that separated and divorced persons have a greater likelihood ofdrug use even net ofnegative life bles entered in subsequent stages. Urban chic distress and health care utilization. events and psychic distress, suggesting residence is not strongly associated with However as canbe seen in the final model, other explanatory or predispositional fac- drug use. In stage III the number of neg- effects of DIS diagnoses are mediated by tors, not examined in the present analysis. ative life events is positively and substan- psychic distress. Finallythese analyses raise questions tially associated with drug use. Decreases about associations between symptoms, in this effect in stages IV through VI in- Discussion diagnosis, and appropriate psychothera- dicate that the effect ofnegative life events peutic drug use. There is evidence that the is due primarily to the effects of life stress Multivariate analysis of survey data American public has become more con- on DIS diagnoses, psychic distress symp- indicates that when potential confounding servative in its attitudes toward psycho- toms, and increased health care utiliza- factors are controlled, age, sex, race, ed- tropicdruguse.2,27 In fact, our preliminary tion. In stages IV through VI, affective ucation, and marital status are related to data indicate that the majority of persons disorder, agoraphobia with panic, and benzodiazepine anxiolytic use. Age, race, with high levels of anxiety in the commu- panic disorder are all associated with in- and marital status remain substantially un- nity are not receiving psychotherapeutic creased benzodiazepine use, as are psy- mediated by other factors while sex and medications; further analyses need to ex-

594 American Journal of Public Health May 1991, Vol. 81, No. 5 Prevalence and Correlates ofAndiolytic Use

plore whether they are receiving other variables. In addition we have found ben- 5. Shader RI, Greenblatt DJ: Benzodiazepine psychotherapeutic interventions. There is zodiazepine anxiolytic use to be signifi- overuse-misuse. J Clin Psychopharm 1984; also a association between a DIS 4:123-124. strong cantly associated with several DIS diag- 6. Parry HJ, Balter M, Mellinger G, Cisin I, diagnosis of affective disorder and use of noses although the effects ofdiagnoses are Manheimer D: National patterns of psy- benzodiazepine anxiolytics. Concurrent largely mediated by psychic distress and chotherapeutic drug use. Arch Gen Psychi- use of antidepressants is not examined in use of health services. Future research on atry 1973; 28:769-783. the present study. However, Craig, et al, this population will focus on duration and 7. Uhlenhuth EH, Balter M, Lipman R; Mi- also found that surveyed women taking nor tranquilizers. Arch Gen Psychiatry frequency of anxiolytic use, use of other 1978; 35:650-655. minor tranquilizers and sedatives included psychotropic drugs, and use ofpotentially 8. Mellinger GD, Balter MB, ParryHJ, Man- significantly more respondents with high interacting drug combinations. Finally, heimer DI, Cisin IH: An overview of psy- depression scores, and that depressed re- more detailed DIS diagnostic information chotherapeutic drug use in the United spondents of both sexes tended to be tak- at follow-up of the survey co- States. In: Josephson E, Carroll E (eds): gathered Drug Use: and Sociologi- ing anxiolytics or sedatives, and not anti- hort, including generalized anxiety disor- Epidemiological 29 cal Approaches. New York: Hemisphere, depressants.28 Beardsley, et at found der, will allow closer examination of the 1974; 333-366. that primary care practitioners provided associations between benzodiazepine 9. Mellinger GD, Balter MB, Manheimer DI, 72 percent of all anxiolytic drug visits, but anxiolytic use and DIS diagnoses of affec- Cisin IH, Parry HJ: Psychic distress, life documented a psychiatric diagnosis in a tive and anxiety disorders. [1 crisis, and use of psychotherapeutic medi- minority of anxiolytic drug visits, raising cations. Arch Gen Psychiatry 1978; 35:1045-1052. questions about the specificity of anxi- 10. Mellinger GD, Balter MB, Uhlenhuth EH: olytic use in primary care settings. Al- Prevalence and correlates of the long-term though anxious and depressive symptoms Acknowledgments regular use of anxiolytics. JAMA 1984; are often admixed, the present findings 251:375-379. This study was funded by a grant to the Duke 11. Cottler LB, Robins LN: The prevalence of high anxiolytic use among depressed Department of Psychiatry from NIMH (MH and characteristics of psychoactive medi- respondents suggest that depressive 35386). cation use in a general population study. symptoms are underrecognized. Major Psychopharm Bull 1983; 19:746-751. depressive episodes usually require spe- References 12. Dunbar GC, Perera MH, Jenner FA: Pat- cific antidepressant medication and psy- 1. Baum C, Kennedy DL, Forbes MB, Jones terns of benzodiazepine use in Great Brit- JK. Drug use in the United States in 1981. ain as measured by a general population chotherapy, and treatment with benzodi- JAMA 1984; 251:1293-1297. survey. Br J Psychiatry 1989; 155:836-841. azepine anxiolytics in the absence ofmore 2. Mellinger GD, Balter MB: Prevalence and 13. Regier DA, Myers JK, Kramer M, Robins specific antidepressant therapy may post- patterns ofuse ofpsychotherapeutic drugs: LN, Blazer DG, Hough RL, Eaton WW, pone therapeutic response or even exac- Results from a 1979 national survey of Locke BZ: The NIMH Epidemiologic erbate American adults. In: Tognoni G, Bellan- Catchment Area Program. Arch Gen Psy- symptoms.23,30,31 tuono C, Lader M (eds): Impact ofPsycho- chiatry 1984; 41:934-941. We have examined the current prev- tropic Drugs. Elsevier, North Holland Bio- 14. Kish L: SurveySampling. New York: John alence ofbenzodiazepine anxiolytic use in medical Press, 1981; 117-135. Wiley and Sons, 1965. a Southern community, demonstrating 3. Klerman GL: Psychotropic hedonism vs 15. Blazer DG, George LK, Landerman R, that age, sex, race, education, and marital pharmacological calvinism, The Hastings Pennybacker M, Melville ML, Woodbury Report 1972; 2:1-3. M, Manton KG, Jordan K, Locke B: Psy- status are significantly associated with 4. Baum C, Kennedy DL, Forbes MB, Jones chiatric disorders: A rural/urban compari- drug use, but that the effects of sex and JK: Drug use and expenditures in 1982. son. Arch Gen Psychiatry 1985; 42:651- education are mediated by intervening JAMA 1985; 253:382-386. 656.

May 1991, Vol. 81, No. 5 American Journal of Public Health 595 Swartz et al.

16. Robins LN, Helzer JE, Croughan J, Rat- 26. Ray WA, Grfin MR, Downey W: Benzo- 29. Beardsley RS, Gardockd GJ, Larson DB, cliff KF: National Institute of Mental diazepines of long and short elimination Hidalgo J: Prescribing of psychotropic Health Diagnostic Interview Schedule: Its half-life and the risk of hip fracture. JAMA medication by primary care physicians and history, characteristics and validity. Arch 1989; 262:3303-3307. psychiatrists. Arch Gen Psychiatry 1988; Gen Psychiatry 1981; 38:381-389. 27. Manheimer DI, Davidson ST, Balter MB, 45:1117-1119. 17. Derogatis LP, Lipman RS, Covi L: SCL- Mellinger GD, Cisin IH, Parry HJ: Popular attitudes and beliefs about tranquilizers. 30. Hall RCW, Joffe JR: Aberrant response to 90: An outpatient psychiatric rating scale: diazepam: A new syndrome. Am J Psychi- Preliminary report. Psychopharm Bull Am J Psychiatry 1973; 130:1246-1253. 1973; 9:13-28. 28. Craig TJ, Van Netta PA: Current medica- atry 1972; 129:738-742. 18. Holmes TH, Rahe RH: The Social Re- tion use and symptoms of depression in a 31. Greenblatt DJ, Shader RI: Benzodiaz- adjustment Rating Scale. J Psychosom Res general population. Am J Psychiatry 1978; epines in Clinical Practice. New York: 1967; 11:213-218. 135:1036-1039. Raven Press, 1974. 19. Hughes DC, Blazer DG, George LK Age differences in life events: A multivariate controlled analysis. IntJAgingHuman De- vel 1988; 27:207-220. 20. Hughes DC, George LK, Blazer DG: Age differencesinlife event qualities: Multivari- ate controlled analyses. J Community Psy- chology 1988; 16:161-174. 21. Hanushek EA, Jackson JE: Statistical Methods for Social Scientists. New York: Academic Press, 1977. 22. Harrell FE: The LOGIST Procedure. Ix Joyner S (ed): Supplemental -ibrary Us- er's Guide, 1983 Edition. Cary, NC: SAS Institute, Inc, 1983. 23. Rickels K: Use of antianxiety agents in anxious outpatients. Psychopharmacology 1978; 58:1-17. 24. Berg RH: The over-medicated woman. McCall's 1971; 67:109-111. 25. RogersJM: Stimulus/response: Drug abuse byprescription. Psychol Today 1971; 5:16- 24.

596 American Journal of Public Health May 1991, Vol. 81, No. 5